Circuit micropatterning and an increase in density require an exposure apparatus for manufacturing a device to project a circuit pattern formed on a reticle onto a wafer at a higher resolving power. The circuit pattern resolving power depends on the wavelength of exposure light and the NA (Numerical Aperture) of a projection optical system for projecting a reticle pattern onto a wafer. The resolving power is increased by increasing the NA of the projection optical system or shortening the wavelength of exposure light. As for the latter method, the exposure light source is shifting from a g-line lamp to an i-line lamp, and further from the i-line lamp to an excimer laser. As the excimer laser, a KrF excimer laser and an ArF excimer laser having oscillation wavelengths of 248 nm and 193 nm, respectively, are available and have already been used as a light source for an exposure apparatus.
At present, a VUV (Vacuum Ultra Violet) exposure apparatus using an F2 excimer laser with a shorter oscillation wavelength of 157 nm, and an EUV (Extreme Ultra Violet) exposure apparatus using an EUV light source (e.g., a laser plasma light source, pinch plasma light source, or synchrotron light source) with a wavelength of 13 nm are examined as next-generation exposure apparatuses.
Along with circuit micropatterning, demands have also arisen for aligning at a high precision a reticle on which a circuit pattern is formed and a wafer onto which the circuit pattern is projected. The necessary precision is generally ⅓ the circuit line width. For example, the necessary precision in a 180-nm design rule is ⅓, i.e., 60 nm.
Various device structures have been proposed and examined for commercial use. With the spread of personal computers and the like, micropatterning has shifted from memories such as a DRAM to CPU chips. For further IT revolution, circuits will be further micropatterned by the development of MMIC (Millimeter-wave Monolithic Integrated Circuits), and the like, used in communication system devices called a home wireless LAN and Bluetooth, highway traffic systems (ITS: Intelligent Transport Systems) represented by a car radar using a frequency of 77 GHz, and wireless access systems (LMDS: Local Multipoint Distribution Service) using a frequency of 24 GHz to 38 GHz.
There are also proposed various semiconductor device manufacturing processes. As a planarization technique which solves an insufficient depth of the exposure apparatus, the W-CMP (Tungsten Chemical Mechanical Polishing) process has already been a past technique. Instead, the Cu dual damascene process has received a great deal of attention.
Various semiconductor device structures and materials are used. For example, there are proposed a P-HEMT (Pseudomorphic High Electron Mobility Transistor) and M-HEMT (Metamorphe-HEMT) which are formed by combining compounds such as GaAs and InP, and an HBT (Heterojunction Bipolar Transistor) using SiGe, SiGeC, and the like.
Under the present circumstance of the semiconductor industry, many apparatus parameters must be set in correspondence with each exposure method and each product in the use of a semiconductor manufacturing apparatus such as an exposure apparatus. The parameters are not independent of each other but are closely related to each other.
These parameter values have conventionally been decided by trial and error by the person in charge of a device manufacturer. A long time is taken to decide optimal parameter values. If, e.g., a process error occurs after the parameter values are decided, the manufacturing process is changed in accordance with the error. With this change, the parameter values of the manufacturing apparatus must be changed again. Also, in this case, a long time is taken to decide optimal parameter values.
In the semiconductor device production, the time which can be taken until the start of volume production after the activation of a manufacturing apparatus is limited. The time which can be taken to decide the parameter value of each parameter is also limited. In terms of CoO (Cost of Ownership), the operating time of the manufacturing apparatus must be prolonged. To change a parameter value which has already been decided, it must be quickly changed. In this situation, it is very difficult to manufacture various semiconductor devices with an optimal parameter value of each parameter. Even a manufacturing apparatus which can originally achieve a high yield is used without optimizing the parameter value of each parameter, decreasing the yield. Such low yield leads to a high manufacturing cost, a small shipping amount, and weak competitiveness.